OBJECTIVE To design and synthesize rifamycin S derivatives and load them into milk exosomes to evaluate their in vitro antimicrobial activity.METHODS Rifamycin S derivatives were synthe-sized and characterized by mass spectrometry and NMR.Using the dilution assay method,the inhibitory activity of each rifamycin S derivatives molecule against Staphylococcus aureus and Pseudomonas aerugi-nosa was determined,and the IC50 was calculated.Derivatives molecules with excellent antimicrobial activity were selected and loaded into milk exosomes using the ultrasonication method,resulting in the preparation of milk exosome-loaded rifamycin S derivatives.The antimicrobial activity against Staphylo-coccus aureus was determined using the dilution assay method.The inhibitory effect of the exosome-loaded rifamycin S derivatives on Staphylococcus aureus residing within macrophages was detected using the plate colony counting method.RESULTS Three rifamycin S derivatives were successfully designed and synthesized,which demonstrated superior antimicrobial activity against Staphylococcus aureus(the parent compound's antimicrobial activity is merely from 1/20 to 1/80 of that of the three rifamycin S derivatives)and Pseudomonas aeruginosa(the parent compound's antimicrobial activity is only 1/14 and 1/9 of that of compound 1 and compound 3)compared to the parent compound.The loading of milk exosomes with the rifamycin S derivatives compound 3 was successfully achieved,with a loading efficiency of 10.9％.The antimicrobial activity of the compound after exosome loading was significantly enhanced against Staphylococcus aureus in vitro and against Staphylococcus aureus residing within macrophages(P＜0.01).CONCLUSION The designed and synthesized derivatives of rifamycin S possess stronger anti-microbial activity,and their antibacterial efficacy against both extracellular and intracellular bacteria can be further enhanced after loading into exosomes.

AIM:To investigate the immunosuppressive effects of M2-like tumor-associated macrophages(M2-TAMs)on CD8+T cells within the tumor microenvironment of esophageal cancer.METHODS:Multiplex fluores-cence immunohistochemistry was used to analyze the distribution of immune cells in esophageal cancer tissues.An in vitro co-culture system was established,and flow cytometry along with Calcein-AM/PI staining was employed to assess the im-pact of M2-TAMs on CD8+T cell function.The GEPIA database was utilized to evaluate the prognostic significance of PDCD1 expression in esophageal cancer patients and to analyze the correlations between gene expressions.Immunohisto-chemistry(IHC)was performed to detect the expression of TGF-β1 in esophageal cancer tissues.Flow cytometry and en-zyme-linked immunosorbent assay(ELISA)were used to measure PD-1,IFN-γ and TNF-α expression in CD8+T cells fol-lowing treatment with a TGF-β1 inhibitor.RESULTS:Compared with early-stage(stage I)esophageal cancer patients,the patients with advanced disease(stages Ⅱ to Ⅳ)exhibited dynamic changes in the infiltration of CD4+T cells,CD8+T cells,Tregs,and M2-TAMs within tumor tissues,with significant correlations observed among these cell populations(P<0.05).The distribution of M2-TAMs and Tregs was positively correlated with poor prognosis(P<0.05),while that of CD8+T cells was negatively correlated(P<0.05).In contrast,CD4+T cell infiltration showed no significant association with clinical outcomes(P>0.05).Co-culture of CD8+T cells with M2-TAMs resulted in significant downregulation of CD107a,granzyme B,IFN-γ and TNF-α expression(P<0.01).Additionally,M2-TAM-treated CD8+T cells co-cultured with esophageal cancer cells led to reduced apoptosis of cancer cells.High expression of PDCD1 was significantly associated with poor prognosis(P<0.05),and significant correlations were observed between CD8A and PDCD1 expression,as well as between TGF-β1 and CD274 gene expression(P<0.01).TGF-β1 was also significantly associated with CD163+macro-phage infiltration and the progression of esophageal cancer(P<0.05).Treatment with a TGF-β1 inhibitor in the M2-TAM and CD8+T cell co-culture system significantly down-regulated PD-1 expression and increased the secretion of IFN-γ and TNF-α(P<0.01).CONCLUSION:The TGF-β1 derived from M2-TAMs inhibits the antitumor activity of CD8+T cells in the esophageal cancer microenvironment,suggesting potential therapeutic targets for overcoming immunosuppression in esophageal cancer.

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With the main pathological features of glomerulosclerosis and interstitial fibrosis， renal fibrosis is a key pathological process causing chronic kidney disease to progress to end-stage disease. As a cellular autophagic process， mitochondrial autophagy plays a crucial role in maintaining mitochondrial mass and functional stability. Mitochondrial dysfunction is considered to be one of the key factors driving the progression of fibrosis. Phosphatase and tension protein homologue （PTEN） induce various signalling pathways such as putative kinase 1/parkin， Nip3-like protein X/Bcl-2 interacting protein 3， and FUN14 structural domain-containing protein 1 to activate mitochondrial autophagy to participate in the regulation of fibrogenic factors， amelioration of oxidative stress， and inhibition of inflammatory response and apoptosis， which in turn effectively slows down the progression of renal fibrosis. Studies have shown that traditional Chinese medicine monomers and compound preparations， including phenolics， terpenoids， ketones， and alkaloids， can regulate mitochondrial autophagy-related signalling pathways and achieve significant clinical efficacy in intervening in the progression of renal fibrosis for the treatment of chronic kidney disease. This paper summarized the mechanism of mitochondrial autophagy and the research progress of traditional Chinese medicine intervention in renal fibrosis to provide new ideas for the study of the mechanism of traditional Chinese medicine in treating renal fibrosis.

With the main pathological features of glomerulosclerosis and interstitial fibrosis， renal fibrosis is a key pathological process causing chronic kidney disease to progress to end-stage disease. As a cellular autophagic process， mitochondrial autophagy plays a crucial role in maintaining mitochondrial mass and functional stability. Mitochondrial dysfunction is considered to be one of the key factors driving the progression of fibrosis. Phosphatase and tension protein homologue （PTEN） induce various signalling pathways such as putative kinase 1/parkin， Nip3-like protein X/Bcl-2 interacting protein 3， and FUN14 structural domain-containing protein 1 to activate mitochondrial autophagy to participate in the regulation of fibrogenic factors， amelioration of oxidative stress， and inhibition of inflammatory response and apoptosis， which in turn effectively slows down the progression of renal fibrosis. Studies have shown that traditional Chinese medicine monomers and compound preparations， including phenolics， terpenoids， ketones， and alkaloids， can regulate mitochondrial autophagy-related signalling pathways and achieve significant clinical efficacy in intervening in the progression of renal fibrosis for the treatment of chronic kidney disease. This paper summarized the mechanism of mitochondrial autophagy and the research progress of traditional Chinese medicine intervention in renal fibrosis to provide new ideas for the study of the mechanism of traditional Chinese medicine in treating renal fibrosis.

Objective:To investigate the anti-leukemic effects and resistance mechanisms of venetoclax in acute myeloid leukemia (AML). Genomic, transcriptomic, and clinical data from AML patients who underwent venetoclax drug sensitivity testing were downloaded from the Beat AML database. Correlation analysis was performed between these data and venetoclax sensitivity outcomes. Differentially expressed genes (DEGs) associated with venetoclax sensitivity were identified from transcriptomic data and subsequently validated using GEO database transcriptomic results and in vitro experiments (including Western blot). Functional enrichment analyses (KEGG and GSEA), transcription factor enrichment analysis (KnockTF), and data from public databases were employed to further investigate key genes and pathways influencing drug sensitivity.Results:After filtering the Beat AML cohort, data from 52 patient samples with available in vitro venetoclax sensitivity results were included for analysis. Patients with FLT3 mutations exhibited greater sensitivity to venetoclax compared to those with FLT3 wild-type. Correlation analysis between clinical information and drug sensitivity data indicated that higher peripheral blood tumor burden was associated with increased sensitivity to venetoclax. Transcriptomic analysis and in vitro experiments confirmed that venetoclax inhibits the FLT3-related signaling pathway, including downregulation of FLT3 expression and reduced phosphorylation of its downstream targets AKT and STAT5. KEGG pathway and KnockTF transcription factor enrichment analyses indicated that venetoclax resistance was associated with increased transcriptional activity of FOXM1 and STAT3. Moreover, high expression of FOXM1 and STAT3 correlated with shorter overall survival in patients.Conclusion:Venetoclax can inhibit the activation of FLT3-related signaling pathways. The activation of STAT3 and FOXM1 transcription factors is a potential key mechanism contributing to venetoclax resistance in AML.

Objective:To investigate the anti-leukemic effects and resistance mechanisms of venetoclax in acute myeloid leukemia (AML). Genomic, transcriptomic, and clinical data from AML patients who underwent venetoclax drug sensitivity testing were downloaded from the Beat AML database. Correlation analysis was performed between these data and venetoclax sensitivity outcomes. Differentially expressed genes (DEGs) associated with venetoclax sensitivity were identified from transcriptomic data and subsequently validated using GEO database transcriptomic results and in vitro experiments (including Western blot). Functional enrichment analyses (KEGG and GSEA), transcription factor enrichment analysis (KnockTF), and data from public databases were employed to further investigate key genes and pathways influencing drug sensitivity.Results:After filtering the Beat AML cohort, data from 52 patient samples with available in vitro venetoclax sensitivity results were included for analysis. Patients with FLT3 mutations exhibited greater sensitivity to venetoclax compared to those with FLT3 wild-type. Correlation analysis between clinical information and drug sensitivity data indicated that higher peripheral blood tumor burden was associated with increased sensitivity to venetoclax. Transcriptomic analysis and in vitro experiments confirmed that venetoclax inhibits the FLT3-related signaling pathway, including downregulation of FLT3 expression and reduced phosphorylation of its downstream targets AKT and STAT5. KEGG pathway and KnockTF transcription factor enrichment analyses indicated that venetoclax resistance was associated with increased transcriptional activity of FOXM1 and STAT3. Moreover, high expression of FOXM1 and STAT3 correlated with shorter overall survival in patients.Conclusion:Venetoclax can inhibit the activation of FLT3-related signaling pathways. The activation of STAT3 and FOXM1 transcription factors is a potential key mechanism contributing to venetoclax resistance in AML.

Objective:To investigate the expressions of cystathionine-β-synthase(CBS)and cystathionine-γ-lyase(CSE)and their effects on the malignant biological behaviours of breast cancer cells,and to elucidate their mechanisms.Methods:The breast cancer tissue and paracancerous normal tissue from 15 cases of patients were selected,and RT-qPCR and Western blotting methods were used to detect the mRNA and protein expression levels of CBS and CSE in breast cancer tissue,paracancerous normal tissue,MCF-7 cells,and MDA-MB-231 cells.The MCF-7 cells were divided into siNC group(transfected with siNC)and siCBS group(transfected with siCBS),and the MDA-MB-231 cells were divided into ovNC group(transfected with CSE over-expression empty plasmid)and ovCSE group(transfected with CSE over-expression plasmid).CCK8 assay was used to detect the proliferation activities of breast cancer cells in various groups,Transwell assay was used to detect the numbers of migration and invasion cells in various groups,and Western blotting method was used to detect the protein expression levels of E-cadherin,N-cadherin and Vimentin proteins in the breast cancer cells in various groups.Results:Compared with paracancerous normal tissue,the expression levels of CBS and CSE mRNA and proteins in breast cancer tissue were increased(P＜0.05 or P＜0.01).Compared with MDA-MB-231 cells,the CBS mRNA expression level in the MCF-7 cells was increased(P＜0.05);compared with MCF-7 cells,the expression level of CSE protein in the MDA-MB-231 cells was decreased(P＜0.05).Compared with siNC group,the proliferation activity,the numbers of migration and invasion cells,the expression levels of N-cadherin and Vimentin proteins in the MCF-7 cells in siCBS group were significantly decreased(P＜0.05),and the expression level of E-cadherin protein was increased(P＜0.05).Compared with ovNC group,the proliferation activity,the numbers of migratoin and invasion cells,and the expression levels of N-cadherin and Vimentin proteins in the MDA-MB-231 cells in ovCSE group were increased(P＜0.05),while the expression level of E-cadherin protein was significantly decreased(P＜0.05).Conclusion:The expressions of CBS and CSE are upregulated in breast cancer tissue,and high levels of CBS and CSE promote proliferation,migration,invasion and epithelial-mesenchymal transition(EMT)of breast cancer cells.

AIM:To investigate the immunosuppressive effects of M2-like tumor-associated macrophages(M2-TAMs)on CD8+T cells within the tumor microenvironment of esophageal cancer.METHODS:Multiplex fluores-cence immunohistochemistry was used to analyze the distribution of immune cells in esophageal cancer tissues.An in vitro co-culture system was established,and flow cytometry along with Calcein-AM/PI staining was employed to assess the im-pact of M2-TAMs on CD8+T cell function.The GEPIA database was utilized to evaluate the prognostic significance of PDCD1 expression in esophageal cancer patients and to analyze the correlations between gene expressions.Immunohisto-chemistry(IHC)was performed to detect the expression of TGF-β1 in esophageal cancer tissues.Flow cytometry and en-zyme-linked immunosorbent assay(ELISA)were used to measure PD-1,IFN-γ and TNF-α expression in CD8+T cells fol-lowing treatment with a TGF-β1 inhibitor.RESULTS:Compared with early-stage(stage I)esophageal cancer patients,the patients with advanced disease(stages Ⅱ to Ⅳ)exhibited dynamic changes in the infiltration of CD4+T cells,CD8+T cells,Tregs,and M2-TAMs within tumor tissues,with significant correlations observed among these cell populations(P<0.05).The distribution of M2-TAMs and Tregs was positively correlated with poor prognosis(P<0.05),while that of CD8+T cells was negatively correlated(P<0.05).In contrast,CD4+T cell infiltration showed no significant association with clinical outcomes(P>0.05).Co-culture of CD8+T cells with M2-TAMs resulted in significant downregulation of CD107a,granzyme B,IFN-γ and TNF-α expression(P<0.01).Additionally,M2-TAM-treated CD8+T cells co-cultured with esophageal cancer cells led to reduced apoptosis of cancer cells.High expression of PDCD1 was significantly associated with poor prognosis(P<0.05),and significant correlations were observed between CD8A and PDCD1 expression,as well as between TGF-β1 and CD274 gene expression(P<0.01).TGF-β1 was also significantly associated with CD163+macro-phage infiltration and the progression of esophageal cancer(P<0.05).Treatment with a TGF-β1 inhibitor in the M2-TAM and CD8+T cell co-culture system significantly down-regulated PD-1 expression and increased the secretion of IFN-γ and TNF-α(P<0.01).CONCLUSION:The TGF-β1 derived from M2-TAMs inhibits the antitumor activity of CD8+T cells in the esophageal cancer microenvironment,suggesting potential therapeutic targets for overcoming immunosuppression in esophageal cancer.

OBJECTIVE To design and synthesize rifamycin S derivatives and load them into milk exosomes to evaluate their in vitro antimicrobial activity.METHODS Rifamycin S derivatives were synthe-sized and characterized by mass spectrometry and NMR.Using the dilution assay method,the inhibitory activity of each rifamycin S derivatives molecule against Staphylococcus aureus and Pseudomonas aerugi-nosa was determined,and the IC50 was calculated.Derivatives molecules with excellent antimicrobial activity were selected and loaded into milk exosomes using the ultrasonication method,resulting in the preparation of milk exosome-loaded rifamycin S derivatives.The antimicrobial activity against Staphylo-coccus aureus was determined using the dilution assay method.The inhibitory effect of the exosome-loaded rifamycin S derivatives on Staphylococcus aureus residing within macrophages was detected using the plate colony counting method.RESULTS Three rifamycin S derivatives were successfully designed and synthesized,which demonstrated superior antimicrobial activity against Staphylococcus aureus(the parent compound's antimicrobial activity is merely from 1/20 to 1/80 of that of the three rifamycin S derivatives)and Pseudomonas aeruginosa(the parent compound's antimicrobial activity is only 1/14 and 1/9 of that of compound 1 and compound 3)compared to the parent compound.The loading of milk exosomes with the rifamycin S derivatives compound 3 was successfully achieved,with a loading efficiency of 10.9％.The antimicrobial activity of the compound after exosome loading was significantly enhanced against Staphylococcus aureus in vitro and against Staphylococcus aureus residing within macrophages(P＜0.01).CONCLUSION The designed and synthesized derivatives of rifamycin S possess stronger anti-microbial activity,and their antibacterial efficacy against both extracellular and intracellular bacteria can be further enhanced after loading into exosomes.